Relay or contactor for 50KHz, 1.9Arms, 342Vrms?

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treez

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I wish to have a relay or contactor which will switch ON/OFF a current that is 1.9A RMS. This current is also sinusoidal and at a frequency of 50 KiloHertz (50000 Hertz).
The peak voltage of this is 483Volts.
That is, the voltage is sinusoidal and 342Vrms.

Do you agree that “normal” relays , that have AC ratings, do not apply here, because their AC ratings always refer to 50Hz rather than 50KHz?

Do you agree that at 50KHz we must look at the DC rating, because at 50KHz, the contact arc is not extinguished when the sine wave goes through zero, because it is reignited as the waveform moves above zero within a few microseconds.

I have found this contactor, and believe it is suitable to switch this waveform, do you agree?

(Farnell 3621819)
Schneider CAD50BD contactor…
https://uk.farnell.com/schneider-electric-telemecanique/cad50bd/relay-control-5no-24vdc/dp/3621819
 

According to the datasheet, the contactor can only switch-off small current (some 100 mA) at 300 or 400 V DC.

DC capable contactors have arc extinguishing means (e.g. magnetical blowing) that won't work for high frequent AC either.

I don't believe that a 50 kHz arc will behave exactly like DC, but I agree that there's probably a problem with standard relays.
 

According to the datasheet, the contactor can only switch-off small current (some 100 mA) at 300 or 400 V DC.

i am not sure which part of the datasheet says this?

Its a pretty "hulking" big contactor, and is rated for 10 Amps, so i'd be surprised if it could only switch 100mA...surely?

I am looking for a parameter called something like "maximum make or break current" but can't find it in the datasheet.....i am wondering if the world of contactors has some different jargon for this meaning?
 

"Contact operating power" diagrams, "broken current"
 
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